busybox/coreutils/cal.c

/* vi: set sw=4 ts=4: */
/*
 * Calendar implementation for busybox
 *
 * See original copyright at the end of this file
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

/* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
/* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect.  The upstream
 * BB_AUDIT BUG: version in util-linux seems to be broken as well. */
/* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */

/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
 *
 * Major size reduction... over 50% (>1.5k) on i386.
 */

#include "busybox.h"

#define	THURSDAY		4		/* for reformation */
#define	SATURDAY		6		/* 1 Jan 1 was a Saturday */

#define	FIRST_MISSING_DAY	639787		/* 3 Sep 1752 */
#define	NUMBER_MISSING_DAYS	11		/* 11 day correction */

#define	MAXDAYS			42		/* max slots in a month array */
#define	SPACE			-1		/* used in day array */

static const char days_in_month[] = {
	0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};

static const char sep1752[] = {
		 1,	2,	14,	15,	16,
	17,	18,	19,	20,	21,	22,	23,
	24,	25,	26,	27,	28,	29,	30
};

static int julian;

/* leap year -- account for Gregorian reformation in 1752 */
#define	leap_year(yr) \
	((yr) <= 1752 ? !((yr) % 4) : \
	(!((yr) % 4) && ((yr) % 100)) || !((yr) % 400))

static int is_leap_year(int year)
{
	return leap_year(year);
}
#undef leap_year
#define leap_year(yr) is_leap_year(yr)

/* number of centuries since 1700, not inclusive */
#define	centuries_since_1700(yr) \
	((yr) > 1700 ? (yr) / 100 - 17 : 0)

/* number of centuries since 1700 whose modulo of 400 is 0 */
#define	quad_centuries_since_1700(yr) \
	((yr) > 1600 ? ((yr) - 1600) / 400 : 0)

/* number of leap years between year 1 and this year, not inclusive */
#define	leap_years_since_year_1(yr) \
	((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))

static void center (char *, int, int);
static void day_array (int, int, int *);
static void trim_trailing_spaces_and_print (char *);

static void blank_string(char *buf, size_t buflen);
static char *build_row(char *p, int *dp);

#define	DAY_LEN		3		/* 3 spaces per day */
#define	J_DAY_LEN	(DAY_LEN + 1)
#define	WEEK_LEN	20		/* 7 * 3 - one space at the end */
#define	J_WEEK_LEN	(WEEK_LEN + 7)
#define	HEAD_SEP	2		/* spaces between day headings */

int cal_main(int argc, char **argv)
{
	struct tm *local_time;
	struct tm zero_tm;
	time_t now;
	int month, year, flags, i;
	char *month_names[12];
	char day_headings[28];	/* 28 for julian, 21 for nonjulian */
	char buf[40];

	flags = getopt32(argc, argv, "jy");

	julian = flags & 1;

	argv += optind;

	month = 0;

	if ((argc -= optind) > 2) {
		bb_show_usage();
	}

	if (!argc) {
		time(&now);
		local_time = localtime(&now);
		year = local_time->tm_year + 1900;
		if (!(flags & 2)) {
			month = local_time->tm_mon + 1;
		}
	} else {
		if (argc == 2) {
			month = xatoul_range(*argv++, 1, 12);
		}
		year = xatoul_range(*argv, 1, 9999);
	}

	blank_string(day_headings, sizeof(day_headings) - 7 +  7*julian);

	i = 0;
	do {
		zero_tm.tm_mon = i;
		strftime(buf, sizeof(buf), "%B", &zero_tm);
		month_names[i] = xstrdup(buf);

		if (i < 7) {
			zero_tm.tm_wday = i;
			strftime(buf, sizeof(buf), "%a", &zero_tm);
			strncpy(day_headings + i * (3+julian) + julian, buf, 2);
		}
	} while (++i < 12);

	if (month) {
		int row, len, days[MAXDAYS];
		int *dp = days;
		char lineout[30];

		day_array(month, year, dp);
		len = sprintf(lineout, "%s %d", month_names[month - 1], year);
		printf("%*s%s\n%s\n",
			   ((7*julian + WEEK_LEN) - len) / 2, "",
			   lineout, day_headings);
		for (row = 0; row < 6; row++) {
			build_row(lineout, dp)[0] = '\0';
			dp += 7;
			trim_trailing_spaces_and_print(lineout);
		}
	} else {
		int row, which_cal, week_len, days[12][MAXDAYS];
		int *dp;
		char lineout[80];

		sprintf(lineout, "%d", year);
		center(lineout,
			   (WEEK_LEN * 3 + HEAD_SEP * 2)
			   + julian * (J_WEEK_LEN * 2 + HEAD_SEP
						   - (WEEK_LEN * 3 + HEAD_SEP * 2)),
			   0);
		puts("\n");		/* two \n's */
		for (i = 0; i < 12; i++) {
			day_array(i + 1, year, days[i]);
		}
		blank_string(lineout, sizeof(lineout));
		week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
		for (month = 0; month < 12; month += 3-julian) {
			center(month_names[month], week_len, HEAD_SEP);
			if (!julian) {
				center(month_names[month + 1], week_len, HEAD_SEP);
			}
			center(month_names[month + 2 - julian], week_len, 0);
			printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
			if (!julian) {
				printf("%*s%s", HEAD_SEP, "", day_headings);
			}
			putchar('\n');
			for (row = 0; row < (6*7); row += 7) {
				for (which_cal = 0; which_cal < 3-julian; which_cal++) {
					dp = days[month + which_cal] + row;
					build_row(lineout + which_cal * (week_len + 2), dp);
				}
				/* blank_string took care of nul termination. */
				trim_trailing_spaces_and_print(lineout);
			}
		}
	}

	fflush_stdout_and_exit(0);
}

/*
 * day_array --
 *	Fill in an array of 42 integers with a calendar.  Assume for a moment
 *	that you took the (maximum) 6 rows in a calendar and stretched them
 *	out end to end.  You would have 42 numbers or spaces.  This routine
 *	builds that array for any month from Jan. 1 through Dec. 9999.
 */
static void day_array(int month, int year, int *days)
{
	long temp;
	int i;
	int j_offset;
	int day, dw, dm;

	memset(days, SPACE, MAXDAYS * sizeof(int));

	if ((month == 9) && (year == 1752)) {
		size_t oday = 0;

		j_offset = julian * 244;
		do {
			days[oday+2] = sep1752[oday] + j_offset;
		} while (++oday < sizeof(sep1752));

		return;
	}

	/* day_in_year
	 *	return the 1 based day number within the year
	 */
	day = 1;
	if ((month > 2) && leap_year(year)) {
		++day;
	}

	i = month;
	while (i) {
		day += days_in_month[--i];
	}

	/* day_in_week
	 *	return the 0 based day number for any date from 1 Jan. 1 to
	 *	31 Dec. 9999.  Assumes the Gregorian reformation eliminates
	 *	3 Sep. 1752 through 13 Sep. 1752.  Returns Thursday for all
	 *	missing days.
	 */
	dw = THURSDAY;
	temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1)
		+ day;
	if (temp < FIRST_MISSING_DAY) {
		dw = ((temp - 1 + SATURDAY) % 7);
	} else if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) {
		dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
	}

	if (!julian) {
		day = 1;
	}

	dm = days_in_month[month];
	if ((month == 2) && leap_year(year)) {
		++dm;
	}

	while (dm) {
		days[dw++] = day++;
		--dm;
	}
}

static void trim_trailing_spaces_and_print(char *s)
{
	char *p = s;

	while (*p) {
		++p;
	}
	while (p > s) {
		--p;
		if (!(isspace)(*p)) {	/* We want the function... not the inline. */
			p[1] = '\0';
			break;
		}
	}

	puts(s);
}

static void center(char *str, int len, int separate)
{
	int n = strlen(str);
	len -= n;
	printf("%*s%*s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
}

static void blank_string(char *buf, size_t buflen)
{
	memset(buf, ' ', buflen);
	buf[buflen-1] = '\0';
}

static char *build_row(char *p, int *dp)
{
	int col, val, day;

	memset(p, ' ', (julian + DAY_LEN) * 7);

	col = 0;
	do {
		if ((day = *dp++) != SPACE) {
			if (julian) {
				++p;
				if (day >= 100) {
					*p = '0';
					p[-1] = (day / 100) + '0';
					day %= 100;
				}
			}
			if ((val = day / 10) > 0) {
				*p = val + '0';
			}
			*++p = day % 10 + '0';
			p += 2;
		} else {
			p += DAY_LEN + julian;
		}
	} while (++col < 7);

	return p;
}

/*
 * Copyright (c) 1989, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Kim Letkeman.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */


1	/* vi: set sw=4 ts=4: */
2	/*
3	* Calendar implementation for busybox
4	*
5	* See original copyright at the end of this file
6	*
7	* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
8	*/
9
10	/* BB_AUDIT SUSv3 compliant with -j and -y extensions (from util-linux). */
11	/* BB_AUDIT BUG: The output of 'cal -j 1752' is incorrect. The upstream
12	* BB_AUDIT BUG: version in util-linux seems to be broken as well. */
13	/* http://www.opengroup.org/onlinepubs/007904975/utilities/cal.html */
14
15	/* Mar 16, 2003 Manuel Novoa III (mjn3@codepoet.org)
16	*
17	* Major size reduction... over 50% (>1.5k) on i386.
18	*/
19
20	#include "busybox.h"
21
22	#define THURSDAY 4 /* for reformation */
23	#define SATURDAY 6 /* 1 Jan 1 was a Saturday */
24
25	#define FIRST_MISSING_DAY 639787 /* 3 Sep 1752 */
26	#define NUMBER_MISSING_DAYS 11 /* 11 day correction */
27
28	#define MAXDAYS 42 /* max slots in a month array */
29	#define SPACE -1 /* used in day array */
30
31	static const char days_in_month[] = {
32	0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
33	};
34
35	static const char sep1752[] = {
36	1, 2, 14, 15, 16,
37	17, 18, 19, 20, 21, 22, 23,
38	24, 25, 26, 27, 28, 29, 30
39	};
40
41	static int julian;
42
43	/* leap year -- account for Gregorian reformation in 1752 */
44	#define leap_year(yr) \
45	((yr) <= 1752 ? !((yr) % 4) : \
46	(!((yr) % 4) && ((yr) % 100)) \|\| !((yr) % 400))
47
48	static int is_leap_year(int year)
49	{
50	return leap_year(year);
51	}
52	#undef leap_year
53	#define leap_year(yr) is_leap_year(yr)
54
55	/* number of centuries since 1700, not inclusive */
56	#define centuries_since_1700(yr) \
57	((yr) > 1700 ? (yr) / 100 - 17 : 0)
58
59	/* number of centuries since 1700 whose modulo of 400 is 0 */
60	#define quad_centuries_since_1700(yr) \
61	((yr) > 1600 ? ((yr) - 1600) / 400 : 0)
62
63	/* number of leap years between year 1 and this year, not inclusive */
64	#define leap_years_since_year_1(yr) \
65	((yr) / 4 - centuries_since_1700(yr) + quad_centuries_since_1700(yr))
66
67	static void center (char *, int, int);
68	static void day_array (int, int, int *);
69	static void trim_trailing_spaces_and_print (char *);
70
71	static void blank_string(char *buf, size_t buflen);
72	static char build_row(char p, int *dp);
73
74	#define DAY_LEN 3 /* 3 spaces per day */
75	#define J_DAY_LEN (DAY_LEN + 1)
76	#define WEEK_LEN 20 /* 7 * 3 - one space at the end */
77	#define J_WEEK_LEN (WEEK_LEN + 7)
78	#define HEAD_SEP 2 /* spaces between day headings */
79
80	int cal_main(int argc, char **argv)
81	{
82	struct tm *local_time;
83	struct tm zero_tm;
84	time_t now;
85	int month, year, flags, i;
86	char *month_names[12];
87	char day_headings[28]; /* 28 for julian, 21 for nonjulian */
88	char buf[40];
89
90	flags = getopt32(argc, argv, "jy");
91
92	julian = flags & 1;
93
94	argv += optind;
95
96	month = 0;
97
98	if ((argc -= optind) > 2) {
99	bb_show_usage();
100	}
101
102	if (!argc) {
103	time(&now);
104	local_time = localtime(&now);
105	year = local_time->tm_year + 1900;
106	if (!(flags & 2)) {
107	month = local_time->tm_mon + 1;
108	}
109	} else {
110	if (argc == 2) {
111	month = xatoul_range(*argv++, 1, 12);
112	}
113	year = xatoul_range(*argv, 1, 9999);
114	}
115
116	blank_string(day_headings, sizeof(day_headings) - 7 + 7*julian);
117
118	i = 0;
119	do {
120	zero_tm.tm_mon = i;
121	strftime(buf, sizeof(buf), "%B", &zero_tm);
122	month_names[i] = xstrdup(buf);
123
124	if (i < 7) {
125	zero_tm.tm_wday = i;
126	strftime(buf, sizeof(buf), "%a", &zero_tm);
127	strncpy(day_headings + i * (3+julian) + julian, buf, 2);
128	}
129	} while (++i < 12);
130
131	if (month) {
132	int row, len, days[MAXDAYS];
133	int *dp = days;
134	char lineout[30];
135
136	day_array(month, year, dp);
137	len = sprintf(lineout, "%s %d", month_names[month - 1], year);
138	printf("%*s%s\n%s\n",
139	((7*julian + WEEK_LEN) - len) / 2, "",
140	lineout, day_headings);
141	for (row = 0; row < 6; row++) {
142	build_row(lineout, dp)[0] = '\0';
143	dp += 7;
144	trim_trailing_spaces_and_print(lineout);
145	}
146	} else {
147	int row, which_cal, week_len, days[12][MAXDAYS];
148	int *dp;
149	char lineout[80];
150
151	sprintf(lineout, "%d", year);
152	center(lineout,
153	(WEEK_LEN * 3 + HEAD_SEP * 2)
154	+ julian * (J_WEEK_LEN * 2 + HEAD_SEP
155	- (WEEK_LEN * 3 + HEAD_SEP * 2)),
156	0);
157	puts("\n"); /* two \n's */
158	for (i = 0; i < 12; i++) {
159	day_array(i + 1, year, days[i]);
160	}
161	blank_string(lineout, sizeof(lineout));
162	week_len = WEEK_LEN + julian * (J_WEEK_LEN - WEEK_LEN);
163	for (month = 0; month < 12; month += 3-julian) {
164	center(month_names[month], week_len, HEAD_SEP);
165	if (!julian) {
166	center(month_names[month + 1], week_len, HEAD_SEP);
167	}
168	center(month_names[month + 2 - julian], week_len, 0);
169	printf("\n%s%*s%s", day_headings, HEAD_SEP, "", day_headings);
170	if (!julian) {
171	printf("%*s%s", HEAD_SEP, "", day_headings);
172	}
173	putchar('\n');
174	for (row = 0; row < (6*7); row += 7) {
175	for (which_cal = 0; which_cal < 3-julian; which_cal++) {
176	dp = days[month + which_cal] + row;
177	build_row(lineout + which_cal * (week_len + 2), dp);
178	}
179	/* blank_string took care of nul termination. */
180	trim_trailing_spaces_and_print(lineout);
181	}
182	}
183	}
184
185	fflush_stdout_and_exit(0);
186	}
187
188	/*
189	* day_array --
190	* Fill in an array of 42 integers with a calendar. Assume for a moment
191	* that you took the (maximum) 6 rows in a calendar and stretched them
192	* out end to end. You would have 42 numbers or spaces. This routine
193	* builds that array for any month from Jan. 1 through Dec. 9999.
194	*/
195	static void day_array(int month, int year, int *days)
196	{
197	long temp;
198	int i;
199	int j_offset;
200	int day, dw, dm;
201
202	memset(days, SPACE, MAXDAYS * sizeof(int));
203
204	if ((month == 9) && (year == 1752)) {
205	size_t oday = 0;
206
207	j_offset = julian * 244;
208	do {
209	days[oday+2] = sep1752[oday] + j_offset;
210	} while (++oday < sizeof(sep1752));
211
212	return;
213	}
214
215	/* day_in_year
216	* return the 1 based day number within the year
217	*/
218	day = 1;
219	if ((month > 2) && leap_year(year)) {
220	++day;
221	}
222
223	i = month;
224	while (i) {
225	day += days_in_month[--i];
226	}
227
228	/* day_in_week
229	* return the 0 based day number for any date from 1 Jan. 1 to
230	* 31 Dec. 9999. Assumes the Gregorian reformation eliminates
231	* 3 Sep. 1752 through 13 Sep. 1752. Returns Thursday for all
232	* missing days.
233	*/
234	dw = THURSDAY;
235	temp = (long)(year - 1) * 365 + leap_years_since_year_1(year - 1)
236	+ day;
237	if (temp < FIRST_MISSING_DAY) {
238	dw = ((temp - 1 + SATURDAY) % 7);
239	} else if (temp >= (FIRST_MISSING_DAY + NUMBER_MISSING_DAYS)) {
240	dw = (((temp - 1 + SATURDAY) - NUMBER_MISSING_DAYS) % 7);
241	}
242
243	if (!julian) {
244	day = 1;
245	}
246
247	dm = days_in_month[month];
248	if ((month == 2) && leap_year(year)) {
249	++dm;
250	}
251
252	while (dm) {
253	days[dw++] = day++;
254	--dm;
255	}
256	}
257
258	static void trim_trailing_spaces_and_print(char *s)
259	{
260	char *p = s;
261
262	while (*p) {
263	++p;
264	}
265	while (p > s) {
266	--p;
267	if (!(isspace)(p)) { / We want the function... not the inline. */
268	p[1] = '\0';
269	break;
270	}
271	}
272
273	puts(s);
274	}
275
276	static void center(char *str, int len, int separate)
277	{
278	int n = strlen(str);
279	len -= n;
280	printf("%s%s", (len/2) + n, str, (len/2) + (len % 2) + separate, "");
281	}
282
283	static void blank_string(char *buf, size_t buflen)
284	{
285	memset(buf, ' ', buflen);
286	buf[buflen-1] = '\0';
287	}
288
289	static char build_row(char p, int *dp)
290	{
291	int col, val, day;
292
293	memset(p, ' ', (julian + DAY_LEN) * 7);
294
295	col = 0;
296	do {
297	if ((day = *dp++) != SPACE) {
298	if (julian) {
299	++p;
300	if (day >= 100) {
301	*p = '0';
302	p[-1] = (day / 100) + '0';
303	day %= 100;
304	}
305	}
306	if ((val = day / 10) > 0) {
307	*p = val + '0';
308	}
309	*++p = day % 10 + '0';
310	p += 2;
311	} else {
312	p += DAY_LEN + julian;
313	}
314	} while (++col < 7);
315
316	return p;
317	}
318
319	/*
320	* Copyright (c) 1989, 1993, 1994
321	* The Regents of the University of California. All rights reserved.
322	*
323	* This code is derived from software contributed to Berkeley by
324	* Kim Letkeman.
325	*
326	* Redistribution and use in source and binary forms, with or without
327	* modification, are permitted provided that the following conditions
328	* are met:
329	* 1. Redistributions of source code must retain the above copyright
330	* notice, this list of conditions and the following disclaimer.
331	* 2. Redistributions in binary form must reproduce the above copyright
332	* notice, this list of conditions and the following disclaimer in the
333	* documentation and/or other materials provided with the distribution.
334	* 3. Neither the name of the University nor the names of its contributors
335	* may be used to endorse or promote products derived from this software
336	* without specific prior written permission.
337	*
338	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
339	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
340	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
341	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
342	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
343	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
344	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
345	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
346	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
347	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
348	* SUCH DAMAGE.
349	*/
350
351